1. Field of the Invention
The present invention generally relates to a buffer amplifier, and more particularly to a low-power high-speed output buffer circuit of a display panel source driver.
2. Description of the Prior Art
As resolutions of flat panel displays (such as liquid crystal displays (LCDs)) increase, thousands of output buffer amplifiers or buffer circuits (“buffers”) are being built into single driver integrated circuits (ICs). In order to accommodate the huge amount of buffer amplifiers in a driver IC, the die area that is occupied by each buffer amplifier should be small, and the power, particularly the static power, consumed by each buffer amplifier should be low. Moreover, due to the long time constant of the column lines in a large-size display panel, a small settling time, or equivalently speaking, a large slew rate is necessary to provide sufficient driving capability to drive the large-size panel. In brief, a low-power high-speed output buffer circuit is becoming indispensable to the high-resolution large-size display panel.
As conventional output buffer circuits cannot effectively provide high driving capability with low-power consumption, a need has arisen to propose a novel low-power high-speed output buffer circuit with enhanced slew rate adaptable to high-resolution and/or large-size display panel.